Package org.apache.commons.vfs2.provider

Class AbstractFileSystem

java.lang.Object

org.apache.commons.vfs2.provider.AbstractVfsComponent

org.apache.commons.vfs2.provider.AbstractFileSystem

All Implemented Interfaces:

Closeable, AutoCloseable, FileSystem, VfsComponent

Direct Known Subclasses:

CompressedFileFileSystem, FtpFileSystem, Http4FileSystem, Http5FileSystem, HttpFileSystem, LocalFileSystem, RamFileSystem, SftpFileSystem, TarFileSystem, UrlFileSystem, VirtualFileSystem, ZipFileSystem

public abstract class AbstractFileSystem
extends AbstractVfsComponent
implements FileSystem

A partial FileSystem implementation.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractFileSystem(FileName rootName, FileObject parentLayer, FileSystemOptions fileSystemOptions)	Constructs a new instance.

Method Summary

Modifier and Type	Method	Description
protected abstract void	addCapabilities(Collection<Capability> caps)	Adds the capabilities of this file system.
void	addJunction(String junctionPoint, FileObject targetFile)	Adds a junction to this file system.
void	addListener(FileObject file, FileListener listener)	Adds a listener on a file in this file system.
void	close()	Closes this component.
void	closeCommunicationLink()	Closes the underlying link used to access the files.
protected abstract FileObject	createFile(AbstractFileName name)	Creates a file object.
protected FileObject	decorateFileObject(FileObject file)	Decorates the given file object.
protected void	doCloseCommunicationLink()	Closes the underlying link used to access the files.
protected File	doReplicateFile(FileObject file, FileSelector selector)	Creates a temporary local copy of a file and its descendants.
void	fireFileChanged(FileObject file)	Fires a file changed event.
void	fireFileCreated(FileObject file)	Fires a file create event.
void	fireFileDeleted(FileObject file)	Fires a file delete event.
Object	getAttribute(String attrName)	Gets the attribute with the specified name.
protected FileObject	getFileFromCache(FileName name)	Gets a cached file.
FileSystemManager	getFileSystemManager()	Gets the FileSystemManager used to instantiate this file system.
FileSystemOptions	getFileSystemOptions()	Gets the FileSystemOptions used to instantiate this file system.
double	getLastModTimeAccuracy()	Gets the accuracy of the last modification time.
FileObject	getParentLayer()	Gets the parent layer if this is a layered file system.
FileObject	getRoot()	Gets the root file of this file system.
FileName	getRootName()	Gets the name of the root of this file system.
String	getRootURI()	Gets the root URI specified for this file System.
boolean	hasCapability(Capability capability)	Tests whether this file system has a particular capability.
void	init()	Initializes this component.
boolean	isOpen()	Tests whether this file system has open streams.
boolean	isReleaseable()	Tests whether any files are using this FileSystem.
protected void	notifyAllStreamsClosed()	Called after all file-objects closed their streams.
protected void	putFileToCache(FileObject file)	Adds a file object to the cache.
protected void	removeFileFromCache(FileName name)	Removes a cached file.
void	removeJunction(String junctionPoint)	Removes a junction from this file system.
void	removeListener(FileObject file, FileListener listener)	Removes a listener from a file in this file system.
File	replicateFile(FileObject file, FileSelector selector)	Creates a temporary local copy of a file and its descendants.
FileObject	resolveFile(String nameStr)	Finds a file in this file system.
FileObject	resolveFile(FileName name)	Finds a file in this file system.
void	setAttribute(String attrName, Object value)	Sets the attribute with the specified name.

Methods inherited from class org.apache.commons.vfs2.provider.AbstractVfsComponent

getContext, getLogger, setContext, setLogger

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

AbstractFileSystem

protected AbstractFileSystem(FileName rootName,
 FileObject parentLayer,
 FileSystemOptions fileSystemOptions)

Constructs a new instance.

Parameters:

rootName - The root file name of this file system.

parentLayer - The parent layer of this file system.

fileSystemOptions - Options to build this file system.

Method Details

addCapabilities

protected abstract void addCapabilities(Collection<Capability> caps)

Adds the capabilities of this file system.

Parameters:

caps - collections of Capabilities, can be immutable.

addJunction

public void addJunction(String junctionPoint,
 FileObject targetFile)
                 throws FileSystemException

Adds a junction to this file system.

Specified by:

addJunction in interface FileSystem

Parameters:

junctionPoint - The junction point.

targetFile - The target to add.

Throws:

FileSystemException - if an error occurs.

addListener

public void addListener(FileObject file,
 FileListener listener)

Adds a listener on a file in this file system.

Specified by:

addListener in interface FileSystem

Parameters:

file - The FileObject to be monitored.

listener - The FileListener

close

public void close()

Closes this component.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Specified by:

close in interface VfsComponent

Overrides:

close in class AbstractVfsComponent

closeCommunicationLink

public void closeCommunicationLink()

Closes the underlying link used to access the files.

createFile

protected abstract FileObject createFile(AbstractFileName name)
                                  throws Exception

Creates a file object.

This method is called only if the requested file is not cached.

Parameters:

name - name referencing the new file.

Returns:

new created FileObject.

Throws:

Exception - might throw an Exception, which is then wrapped in FileSystemException.

decorateFileObject

protected FileObject decorateFileObject(FileObject file)
                                 throws FileSystemException

Decorates the given file object.

Parameters:

file - the file object.

Returns:

the decorated file object.

Throws:

FileSystemException - if a file system error occurs.

doCloseCommunicationLink

protected void doCloseCommunicationLink()

Closes the underlying link used to access the files.

doReplicateFile

protected File doReplicateFile(FileObject file,
 FileSelector selector)
                        throws Exception

Creates a temporary local copy of a file and its descendants.

Parameters:

file - the start of the tree.

selector - selection what to do with children.

Returns:

replicated root file.

Throws:

Exception - any Exception is wrapped as FileSystemException.

fireFileChanged

public void fireFileChanged(FileObject file)

Fires a file changed event.

This will only happen if you monitor the file using FileMonitor.

Parameters:

file - The FileObject that changed.

fireFileCreated

public void fireFileCreated(FileObject file)

Fires a file create event.

Parameters:

file - The FileObject that was created.

fireFileDeleted

public void fireFileDeleted(FileObject file)

Fires a file delete event.

Parameters:

file - The FileObject that was deleted.

getAttribute

public Object getAttribute(String attrName)
                    throws FileSystemException

Gets the attribute with the specified name. The default implementation simply throws an exception.

Specified by:

getAttribute in interface FileSystem

Parameters:

attrName - The name of the attribute.

Returns:

the Object associated with the attribute or null if no object is.

Throws:

FileSystemException - if an error occurs.

See Also:

• FileContent.getAttribute(java.lang.String)

getFileFromCache

protected FileObject getFileFromCache(FileName name)

Gets a cached file.

Parameters:

name - name to search for.

Returns:

file object or null if not found.

getFileSystemManager

public FileSystemManager getFileSystemManager()

Gets the FileSystemManager used to instantiate this file system.

Specified by:

getFileSystemManager in interface FileSystem

Returns:

the FileSystemManager.

getFileSystemOptions

public FileSystemOptions getFileSystemOptions()

Gets the FileSystemOptions used to instantiate this file system.

Specified by:

getFileSystemOptions in interface FileSystem

Returns:

the FileSystemOptions.

getLastModTimeAccuracy

public double getLastModTimeAccuracy()

Gets the accuracy of the last modification time.

Specified by:

getLastModTimeAccuracy in interface FileSystem

Returns:

milliseconds, 0 means perfectly accurate, > 0 might be off by this value, for examnple, sftp is 1000 milliseconds.

getParentLayer

public FileObject getParentLayer()
                          throws FileSystemException

Gets the parent layer if this is a layered file system.

Specified by:

getParentLayer in interface FileSystem

Returns:

The FileObject for the parent layer.

Throws:

FileSystemException - if an error occurs.

getRoot

public FileObject getRoot()
                   throws FileSystemException

Gets the root file of this file system.

Specified by:

getRoot in interface FileSystem

Returns:

The root FileObject of the FileSystem

Throws:

FileSystemException - if an error occurs.

getRootName

public FileName getRootName()

Gets the name of the root of this file system.

Specified by:

getRootName in interface FileSystem

Returns:

the root FileName.

getRootURI

public String getRootURI()

Gets the root URI specified for this file System.

Specified by:

getRootURI in interface FileSystem

Returns:

The root URI used in this file system.

Since:

2.0

hasCapability

public boolean hasCapability(Capability capability)

Tests whether this file system has a particular capability.

Specified by:

hasCapability in interface FileSystem

Parameters:

capability - the Capability to check for.

Returns:

true if the FileSystem has the Capability, false otherwise.

init

public void init()
          throws FileSystemException

Initializes this component.

Specified by:

init in interface VfsComponent

Overrides:

init in class AbstractVfsComponent

Throws:

FileSystemException - if an error occurs.

isOpen

public boolean isOpen()

Tests whether this file system has open streams.

Returns:

true if the FileSystem has open streams.

isReleaseable

public boolean isReleaseable()

Tests whether any files are using this FileSystem.

Returns:

whether any files are using this FileSystem.

notifyAllStreamsClosed

protected void notifyAllStreamsClosed()

Called after all file-objects closed their streams.

putFileToCache

protected void putFileToCache(FileObject file)

Adds a file object to the cache.

Parameters:

file - the file to add.

removeFileFromCache

protected void removeFileFromCache(FileName name)

Removes a cached file.

Parameters:

name - The file name to remove.

removeJunction

public void removeJunction(String junctionPoint)
                    throws FileSystemException

Removes a junction from this file system.

Specified by:

removeJunction in interface FileSystem

Parameters:

junctionPoint - The junction point.

Throws:

FileSystemException - if an error occurs

removeListener

public void removeListener(FileObject file,
 FileListener listener)

Removes a listener from a file in this file system.

Specified by:

removeListener in interface FileSystem

Parameters:

file - The FileObject to be monitored.

listener - The FileListener

replicateFile

public File replicateFile(FileObject file,
 FileSelector selector)
                   throws FileSystemException

Creates a temporary local copy of a file and its descendants.

Specified by:

replicateFile in interface FileSystem

Parameters:

file - The FileObject to replicate.

selector - The FileSelector.

Returns:

The replicated File.

Throws:

FileSystemException - if an error occurs.

resolveFile

public FileObject resolveFile(FileName name)
                       throws FileSystemException

Finds a file in this file system.

Specified by:

resolveFile in interface FileSystem

Parameters:

name - The name of the file to locate.

Returns:

The located FileObject or null if none could be located.

Throws:

FileSystemException - if an error occurs.

resolveFile

public FileObject resolveFile(String nameStr)
                       throws FileSystemException

Finds a file in this file system.

Specified by:

resolveFile in interface FileSystem

Parameters:

nameStr - The name of the file to resolve.

Returns:

The located FileObject or null if none could be located.

Throws:

FileSystemException - if an error occurs.

setAttribute

public void setAttribute(String attrName,
 Object value)
                  throws FileSystemException

Sets the attribute with the specified name. The default implementation simply throws an exception.

Specified by:

setAttribute in interface FileSystem

Parameters:

attrName - the attribute name.

value - The object to associate with the attribute.

Throws:

FileSystemException - if an error occurs.

See Also:

• FileContent.setAttribute(java.lang.String, java.lang.Object)